[INFO] crate mackerel_plugin_uptime 0.1.0 is already in cache
[INFO] checking mackerel_plugin_uptime-0.1.0 against try#1a608893c03d7722effeb0058e82770bd36b4b3c for pr-66504-1
[INFO] extracting crate mackerel_plugin_uptime 0.1.0 into /workspace/builds/worker-3/source
[INFO] validating manifest of crates.io crate mackerel_plugin_uptime 0.1.0 on toolchain 1a608893c03d7722effeb0058e82770bd36b4b3c
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1a608893c03d7722effeb0058e82770bd36b4b3c" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate mackerel_plugin_uptime 0.1.0
[INFO] finished tweaking crates.io crate mackerel_plugin_uptime 0.1.0
[INFO] tweaked toml for crates.io crate mackerel_plugin_uptime 0.1.0 written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1a608893c03d7722effeb0058e82770bd36b4b3c" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1a608893c03d7722effeb0058e82770bd36b4b3c" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=0" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1a608893c03d7722effeb0058e82770bd36b4b3c" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 9208f787d26c35ea445078cc7ced62f7f827a8a645fcbcbfd5eae5c4ebc95162
[INFO] running `"docker" "start" "-a" "9208f787d26c35ea445078cc7ced62f7f827a8a645fcbcbfd5eae5c4ebc95162"`
[INFO] [stderr]     Checking uptime_lib v0.0.0
[INFO] [stderr]     Checking mackerel_plugin v0.2.3
[INFO] [stderr] error[E0284]: type annotations needed: cannot resolve `<std::string::String as std::ops::Add<&_>>::Output == std::string::String`
[INFO] [stderr]    --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/mackerel_plugin-0.2.3/src/lib.rs:306:50
[INFO] [stderr]     |
[INFO] [stderr] 306 | ...                   prefix.clone() + "." + graph.name.as_ref()
[INFO] [stderr]     |                                            ^
[INFO] [stderr] 
[INFO] [stderr] error[E0282]: type annotations needed
[INFO] [stderr]    --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/mackerel_plugin-0.2.3/src/lib.rs:363:93
[INFO] [stderr]     |
[INFO] [stderr] 363 |             let name = if prefix.is_empty() { metric_name } else { prefix.to_string() + "." + metric_name.as_ref() };
[INFO] [stderr]     |                                                                                             ^ cannot infer type
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 2 previous errors
[INFO] [stderr] 
[INFO] [stderr] Some errors have detailed explanations: E0282, E0284.
[INFO] [stderr] For more information about an error, try `rustc --explain E0282`.
[INFO] [stderr] error: could not compile `mackerel_plugin`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "9208f787d26c35ea445078cc7ced62f7f827a8a645fcbcbfd5eae5c4ebc95162"`
[INFO] running `"docker" "rm" "-f" "9208f787d26c35ea445078cc7ced62f7f827a8a645fcbcbfd5eae5c4ebc95162"`
[INFO] [stdout] 9208f787d26c35ea445078cc7ced62f7f827a8a645fcbcbfd5eae5c4ebc95162